Great question! For me it's always been some type of sexual yearning. From my early teens on I have for some reason wanted to be a gorgeous woman. Now when I say want to be it's more of a fantasy want to be. Not I'm a woman trapped in a man's body type thing at all. I may have very slight gender identity issues, but for the most part I am happy in my own skin. It's more escapism for me I think. I get aroused while dressed if not before hand. That is not to say I have to have sex when I get dressed. Regardless if I do or not it arouses me none the less. There is a certain type of woman I find attractive and I guess envy in a way. So I kind of become her. I have taken it as far as wanting what she would want without going into detail. This probably makes no sense although it's the only way I can explain why I crossdress.